Ullubiyaul (, Ullu Boynaq; ) is a rural locality (a selo) in Karabudakhkentsky District, Republic of Dagestan, Russia. The population was 3,666 as of 2010. There are 39 streets.
Ullubiyaul is located 42 km northwest of Novokayakent (the district's administrative centre) by road. Achi-Su and Achi are the nearest rural localities.
Kumyks live there.